In a current communication system, a study for providing services having various Quality of Services (QoS) of high speed to users is in active progress. Recently, research and development of a broadband wireless communication system called a 4-th Generation (4G) communication system, such as a wireless Local Area Network (LAN) system and a wireless Metropolitan Area Network (MAN), or an Institute of Electrical and Electronics Engineers (IEEE) 802.16e communication system are in active progress.
FIG. 1 illustrates a view of a conventional broadband wireless communication system.
Referring to FIG. 1, Access Control Routers (ACRs) 120 and 122 of the broadband wireless communication system are connected with an Internet Protocol (IP) Network 130, and Base Stations (BSs) 110 to 116. The ACRs 120 and 122 transmit/receive data to/from Mobile Stations (MSs) 100 to 106 via a wireless interface at a wired network terminal. That is, the ACRs 120 and 122 control the MSs 100 to 106, and the BSs 110 to 116, and route an IP packet. Additionally, the ACRs 120 and 122 cooperate with the BSs 110 and 116, manage mobility of the MSs 100 to 106, generate/inform charging and statistical information, provide QoS, and manage/control authentication/security and wireless resources. Each of the BSs 110 to 116 is connected with the MSs 100 to 106 for receiving a subscriber service to form a wireless section. The BSs 110 to 116 perform a call process for setting, maintaining, and releasing call connection of a packet, and are responsible for a handover, a system control, and matching of an additional device.
When a message to be transmitted/received is lost, an error occurs during a handover, or an error occurs in an internal resource of the BS 110 while the BS 110 and the MS 100 transmit/receive data to/from each other, a resource allocated by the BS 110 to the MS 100 that is in an active state may be deleted due to resource state mismatching between the BS 110 and the MS 100. A phenomenon that a resource allocated to the MS 100 is improperly deleted may occur in various circumstances besides the above-described case.
When the resource is deleted, the MS 100 cannot receive a data service. When the MS 100 has data or a message to be transmitted to an uplink, the MS 100 transmits a Bandwidth Request Header (BRHdr) requesting a BS to allocate a bandwidth in order to obtain an uplink allocation. At this point, the BS 110 that has received the BRHdr determines a Basic Connection IDentifier (BCID) included in the BRHdr, and ignores the bandwidth allocation request because a currently allocated resource does not exist in the MS 100. Here, the BCID is an identifier of the MS used when the MS performs an initial ranging and transmits/receives a Media Access Control (MAC) management message.
When the above-described procedure continues, the MS 100 cannot receive a service any more, and repeatedly and constantly transmits the BRHdr to the BS 110. This is because the MS 100 cannot recognize a state mismatching between the MS 100 and the BS 110. To resolve this mismatching, an event, such as re-authentication and network re-entry, should occur. However, under the above-described circumstance, the state mismatching between the MS 100 and the BS 110 cannot be resolved because the MS 100 cannot detect a current state.